spidermites.. i just use a yates buggun... or a confidor bug gun.. works well just repeat 3 days later to be sure... best to get the mite problem sorted now before flowering....
Yup, you're right. I gotta deal with the issue now, I was really hoping to avoid the chemicals, but there doesn't seem to be a way around it. I'm wary of pest oil since I used it on my mite infested basil earlier this year and it killed it. I bought some confidor, thanks for the tip.
I'm still very wary of insecticides so I only sprayed one plant today, just to make sure there wont be ill effects, I'll spray the others tommorow.
i've had a few probs in the past with adding the vermiculite , it holds too much water for mj plants ... i changed to perlite and never had any more bother .. ganja plants like to dry out completly .... before being re- watered thus pulling the nutes out of the soil .
I know! i spaced out in bunnings and walked out the door with bags of vermiculite rather than perlite – the packaging is the same, it wasn't till i opened a bag and saw the colour & texture that I realised my mistake.
Hopefully it'll be OK, humidity is fairly low here so the soil will get a chance to dry, I'll have to be careful about it though.
or do what i do in soil
! I think I get what you're saying there Stoney, and I see from your grow threads it works, but i don't think I can circumvent my prissy girly housewife neuroses enough to follow through on that one.
it doesnt seem like a nitrogen deficiency to me as the vast majority of the plant is a lovely green colour and from what i have seen in my own grow room that looks like a classic case of being rootbound but seeing those spots on the leaves + having the pH around 5.5-6.0 has me thinking that the pH is a little lower than what it should be for a soil grow so i would up the pH to around 6.0-6.5 and transplant the plant into a much larger pot
I didn't think N deficiency either due to the dark green colour of the tops, but I'm pretty n00b & given their history it would make sense – I've only fed ¼ to ½ strength nutes once a week. Another point that speaks of N def. is that those 2 pictured are the 2 biggest, most sativa influenced and so probably the 2 hungriest plants. Also the only 2 that have definitely shown sex. I'm thinking if they weren't deficient before they probably are now after yesterday's flushing.
I've repotted both those pictured now, they were a little rootbound, but I wouldn't have thought so grievously as to be dying off like that.
Yeah the PH is definitely too low, I would look at 6.5 - 6.8. You will also find that many potting mixes contain slow release fertilisers which can be harsh on young plants and must be taken into account when fertilising them, when using potting soil I avoid the ones containing them.
The pH is definitely a little on the low side, I've been attempting to correct it by adding dolomite lime to waterings, probably the vermiculite that pushed the pH down – i've read somewhere it's a bit acidic. PH is closer to 6 than 5.5 so should be just within the bounds of acceptable. I'll buy some pH up tomorrow though, it's an easy problem to fix and it'll serve them well in the long term.
The prefert factor was partially what led me to flush initially, thinking it was a salt build up nute lock out.
Just to add to the uncertainty, I have no idea what strain I'm growing, was a bloody nice smoke though.
Possibly the combination of slight acidity, slight rootbinding and N deficiency all collaborated to produce the massive die off?
Hopefully I've got it covered now...
Thanks for all your help guys
I really appreciate all the advice and suggestions.
Edited by Lollygag, 12 November 2006 - 11:34 PM.